A common work machine utilized in the construction field is a tractor loader backhoe which has a loader on the front of the tractor and a backhoe on the rear portion. There are a number of manufacturers of tractors for this purpose as well as bucket styles for the backhoe sections. The variety of equipment has generated a need for universal couplers designed to easily connect the tractor to the bucket of a backhoe assembly. The backhoe buckets are typically attached by a rear mounting pin which is received in a C-shaped slot which may be configured to accommodate a variety of rear pin types. Terms such as “rear”, “front”, “right”, etc. as used herein are from the operator's point of view—typically rearward—away from the loader portion. The front mounting pin configuration for the different bucket styles varies, in terms of pin diameter, spacing from the C-shaped slot, and in the lateral spacing or width of the flanges on the buckets. While a variation of diameter and distance from the C-shaped slot can be readily accommodated, it becomes much more difficult to adapt to a difference in lateral as well as longitudinal pin spacing.
One successful universal coupler for a backhoe assembly is shown in U.S. Pat. No. 9,284,712 wherein a first link is pivotally connected to the articulation joints of the backhoe assembly. Mounting holes for a first and third style bucket with equal lateral pin spacing are provided on the first link. A second link is connected to the first link and is pivotal between a first position in which the mounting holes are exposed and a second position in which the second link covers the holes on the first link and provides the mounting hole diameter and pin spacing for a bucket having a greater pin spacing. This coupler will accommodate either of two buckets of like pin spacing or a third bucket having a greater pin spacing.
What is needed in the art is additional versatility in accommodating backhoe buckets of varying pin spacing, mounting hole location and diameter.